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alkej-395
Cellulose Fibers Dissolution in Alkaline Solution
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In this study, NaOH dissolution method was applied to dissolve cellulose fibers which extracted from date palm fronds (type Al-Zahdi) taken from Iraqi gardens. In this process, (NaOH)-solution is brought into contact with the cellulose fibers at low temperature. Experiments were conducted with different concentrations of NaOH (4%, 6%, 8% and12%) weight percent at two cooling bath temperatures (-15 oC) and (-20oC). Maximum cellulose dissolution was 23 wt% which obtained at 8 wt% concentration of NaOH and at cooling bath temperature of -20oC. In order to enhance the cellulose fibers dissolution, the sample was pretreated with Fenton's reagent which consists of hydrogen peroxide (H2O2), oxalic acid (C2H2O4) and ferrous sulfate (FeSO4). This reagent reacts with cellulose fibers and produces free radicals which increase cellulose dissolution. In this work three variables were studied: cooling bath temperature (-15oCand-20oC), NaOH concentration (4%, 6%, 8% and12%) and time of Fenton's reagent treatment (1-48) hrs. The results showed that the best percent of cellulose dissolution was (42 wt %) which occurred at treatment time (24 hours), temperature (-20oC) and NaOH concentration 8%. In another set of experiments urea was added to NaOH solution as a catalyst with proportion (6%NaOH+4% urea) at two temperatures -15 and -20 oC. The results show that the solubility of cellulose increase to 62% for the sample which treated with Fenton's reagent and to 35% for the untreated sample, both values were obtained at -15oC.

 

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Publication Date
Sun Apr 02 2017
Journal Name
Journal Of Educational And Psychological Researches
" أثر استراتيجية الجيجسو في تحصيل مادة الجغرافيا وعمليات العلم لدى طالبات المرحلة الاعدادية"
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The goal of current researcher to know the impact of strategic Jigsaw in the collection of hypertext and geographic operations of science students at the preparatory stage And that by checking the following 1.There is no difference statistically significant at the significance level 0.05 between the experimental group students who were studying strategy Jigsaw and between the control group students who studied in the usual way traditional degrees in the average achievement in the subject of geographical 2.There is no difference statistically significant at the significance level 0.05 between the experimental group students who were studying strategy Jigsaw and between the control group students who studied in the usual way traditional av

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Publication Date
Sun Jan 01 2012
Journal Name
The Magazine Economics & Admistration
دراسة أنتاج وتسويق التمور في العراق باستعمال طريقة المربعات الصغرى واسلوب البرمجة الخطية
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تناولنا في بحثنا أحد اساليب البرمجة الخطية وهي الطريقة المبسطة لتقدير معلمات انموذج الانحدار الخطي عن طريق اختيار دالة الهدف التي تعمل على تقليل الحد الادنى لمجموع الاخطاء الناتجة من تقدير المعلمات بطريقة المربعات الصغرى الاعتيادية ( OLS) حيث سيتم في الطريقة المبسطة ( simplex) فرض قيود على نفس الاخطاء نفسها بهدف تصغيرها الى اقل ما يمكن للحصول على تقديرات افضل لمعلمات انموذج الانحدار الخطي . على اساس ان طريقة المرب

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Publication Date
Thu Dec 31 2020
Journal Name
Political Sciences Journal
The Trade War Between the United States and China and Its Impact On the World Economy2017-2019
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The trade war, of course, leads to a sharp tension in international relations because the economy is the lifeblood of the states. In the world of trade and economy, countries began to lean towards cooperation. Economic relations after World War II were more liberal, trade barriers were removed and global trade became more flexible and smooth

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Publication Date
Mon Sep 26 2022
Journal Name
جامعة بغداد/ كلية التربية للعلوم الصرفة - ابن الهيثم
مهارات التفكير المعرفي وعلاقته باليقظة العقلية لدى طلبة أقسام الرياضيات في كليات التربية
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Publication Date
Tue Nov 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
Reflection of selection of employee's strategy on human capital/ (Field research at the University of Baghdad)
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Abstract:

This research aims to know the reflection of selection of employees strategy dimensions ( selection of employees strategy standards, procedures selection of employees strategy , efficiency based on a selection of employees strategy) on human capital (knowledge, skills, abilities) in a sample of Lecturers consists of (Deans and assistants and heads of departments) in ( Baghdad University) included nine colleges and university president as total sample size (54), which represent almost 50% of the total research community of 116, was used in the light of the objectives of the research descriptive and analytical approach, has been a resolution main tool for data collection as well as the interview p

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Publication Date
Mon Aug 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
The causal relationship between debt size and Economic value added With contrast of the Frim Size
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Abstract

       The research aims to identify  the  nature of  the relationship between the level of debt used  and economic  value  added  of companies listed on the Iraq Stock Exchange under the Contrast sizes of these companies , The research addressed the theoretical concepts associated with each of the debt financing , economic added value and Organization size With the use of financial techniques in the practical side to measure these variables, The research community Represent of  the shareholding companies listed on the Iraq Stock Exchange with a choice of intentionally sample of 24 joint stock companies representing&nbsp

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Publication Date
Tue Dec 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
The Impact of Combine Level of Capital Structure and Dividend Policy on Firm Stock Price An apply study of companies listed on Amman Stock Exchange
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Although a great deal of works has been done on the area of capital structure and dividend policy, there is still insufficient knowledge of how these policies affect stock prices. This shortcoming may have been originated from the separation between both policies when investigating their effect on stock prices. Based on this point, this research adopts a new technique (completely randomized design), to combine the effect of capital structure and dividend policy on stock prices rather than separating between them. The study used panel based regression analysis depending on the sample of 30 service and industrial Jordanian firms for the period of 2001-2010. The result of test hypotheses found the following; 1) dividend payout has a

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Publication Date
Mon Nov 12 2018
Journal Name
Arab Science Heritage Journal
المادة المادة السابعة في معاهدة باريس لعام 1856 وموقف الدول الأوربية الكبرى منها
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            The issue of the survival of the Ottoman Empire during the nineteenth century, a controversial topic in European diplomacy, was what was called the "Eastern Question" containing the fate of this country and its regions sprawling one of the hottest topics in the diplomatic major European powers of that century

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Publication Date
Wed Sep 25 2019
Journal Name
Journal Of The College Of Education For Women
اثر إستراتيجية شكل البيت الدائري في الأداء التعبيري لدى تلاميذ الصف الخامس الابتدائي
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أجري هذا البحث في العراق/محافظة ديالى، وهدف إلى تعرف أثر إستراتيجية شكل البيت الدائري في الاداء التعبيري لدى تلاميذ الصف الخامس الابتدائي,وبلغت عينة البحث(75) تلميذا بواقع (40) تلميذا في المجموعة التجريبية و(35)تلميذا في المجموعة الضابطة ، وأجرى الباحث بينهما تكافؤا في المتغيرات الآتية (العمر الزمني  محسوبا بالشهور، والتحصيل الدراسي للأبوين ، ودرجات اللغة العربية للعام الدراسي السابق واستعمل الباحث أداة م

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Publication Date
Tue Jul 11 2023
Journal Name
Journal Of Educational And Psychological Researches
A Sociocultural Perspective on Iraqi EFL Learners Reading Comprehension Development
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 Improving speaking skills of Iraqi EFL students was the main purpose of the current research. Thirty EFL students were selected as the research participants for achieving this aim. All students completed the pretest and then spent the next 25 weeks meeting for 90 minutes each to present their nine lectures, answer difficult questions, and get feedback on their use of language in context. Progressive-tests, posttests and delayed post-tests followed every three courses. The researcher utilized SPSS 22 to anal Analyze the data descriptively and inferentially after doing an ANOVA on repeated measurements. It has been shown that using the ideas of sociocultural theory in the classroom has an important and positive impact on students of

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